Cisco IOS XR Software contains a vulnerability that could allow an unauthenticated, remote attacker to cause a denial of service condition. Updates are available.
A vulnerability in the UDP process of Cisco IOS XR Software version 4.3.1 could allow an unauthenticated, remote attacker to cause the UDP process to consume all available packet memory.
The vulnerability is due to the failure of the device to release memory of allocated UDP packets when the packet queues are full. An attacker could exploit this vulnerability by potentially sending traffic to listening UDP services on the affected device. An exploit could allow the attacker to cause the device to exhaust all available memory, causing the device to be unable to allocate memory for packets sent to it.
Cisco has confirmed the vulnerability in a security advisory and released software updates.
Cisco IOS XE Software version 4.3.1 is affected.
To exploit the vulnerability, an attacker must send packets to the targeted device. If access control lists prevent the device from accepting packets from untrusted systems, attackers may be unable to exploit the vulnerability.
An unauthenticated, remote attacker could exploit the vulnerability to cause the device to exhaust all available memory, resulting in a denial of service (DoS) condition.
The vulnerability is due to improper memory operations when processing UDP packets. The affected software fails to release consumed memory.
An unauthenticated, remote attacker could exploit this vulnerability by sending a series of packets to the targeted device. The vulnerability is triggered with packets sent directly to the destination device. Transit packets on the device do not cause a vulnerable condition. The processing of a series of UDP packets could cause the packet memory to be depleted, causing the device to be unable to allocate memory for packets sent to it. As a result, the device may consume all available memory resources, resulting in a DoS condition.
Administrators are advised to apply the appropriate updates.
Administrators may consider using IP-based access control lists (ACLs) to allow only trusted systems to access the affected systems.
Administrators are advised to monitor affected systems.
Cisco customers with active contracts can obtain updates through the Software Center at the following link: Cisco. Cisco customers without contracts can obtain upgrades by contacting the Cisco Technical Assistance Center at 1-800-553-2447 or 1-408-526-7209 or via email at firstname.lastname@example.org.
The security vulnerability applies to the following combinations of products.
Cisco IOS XR Software
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